Question

I’m trying to validate a textarea making sure that each line starts with ‘http://’:

http://jsfiddle.net/n8zYB/1/

When the url is wrong, it executes the else statement but if it’s correct, it isn’t getting executed.

What’s the problem?

Answer 1

It doesn’t work because this refers to a String object. the after function expects a jQuery object or a string. Strangely enough, in javascript strings are different from String objects. Your else statement works because this is being converted into a string behind the scenes when you concat a regular string to it. However, the if fails because this remains a String object in this case. You can fix it in a couple of ways, but here is one of them:

$('button').click(function(){
    var links = $('textarea').val().split('\n');

    $.each(links,function(){
        if( this.substr(0, 7) == 'http://' )
            $('p').after(''+this);
        else
            $('p').after('error: '+this+'<br/>');
    });
    return false;
});

EDIT

here’s a link to another SO question that discusses this in more detail Why are there two kinds of JavaScript strings?